As an example of an optical device, a lighting device is known in which a lens part is formed by performing resin molding on an LED chip mounted on a substrate, and light emitted from the LED chip is concentrated by the lens part. For example, Patent Literature 1 discloses a method for manufacturing an optical-semiconductor electronic component, which makes it easy to mold a lens shape through encapsulation of a light emitting element by, for example, a dispensing method using a silicone resin composition having a specific viscosity and thixotropy.